// Copyright (c) 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef NET_SPDY_SPDY_BUFFER_QUEUE_H_
#define NET_SPDY_SPDY_BUFFER_QUEUE_H_

#include <cstddef>
#include <deque>
#include <memory>

#include "base/macros.h"
#include "net/base/net_export.h"

namespace net {

class SpdyBuffer;

// A FIFO queue of incoming data from a SPDY connection. Useful for
// SpdyStream delegates.
class NET_EXPORT_PRIVATE SpdyReadQueue {
public:
    SpdyReadQueue();
    ~SpdyReadQueue();

    // Returns whether there's anything in the queue.
    bool IsEmpty() const;

    // Returns the total number of bytes in the queue.
    size_t GetTotalSize() const;

    // Enqueues the bytes in |buffer|.
    void Enqueue(std::unique_ptr<SpdyBuffer> buffer);

    // Dequeues up to |len| (which must be positive) bytes into
    // |out|. Returns the number of bytes dequeued.
    size_t Dequeue(char* out, size_t len);

    // Removes all bytes from the queue.
    void Clear();

private:
    std::deque<SpdyBuffer*> queue_;
    size_t total_size_;

    DISALLOW_COPY_AND_ASSIGN(SpdyReadQueue);
};

} // namespace net

#endif // NET_SPDY_SPDY_BUFFER_QUEUE_H_
